Compositions for use in internal-combustion engines and methods of forming and using such compositions

ABSTRACT

A fuel composition for use in internal-combustion engines has a lower grade fuel component, and a microemulsion. The microemulsion includes at least one of hydrous component, renewable component, and polar component being present in an amount effective for forming the fuel composition. The fuel composition may enhance lubricity, corrosion, and water stability without the use of other additives and inhibitors.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Applications, Ser. Nos. 61/798,461 and 61/798,438, each filed Mar. 15, 2013, and each of which is hereby incorporated by reference in its entirety for all purposes. This application is also a continuation of U.S. patent application Ser. No. 13/966,207, filed Aug. 13, 2013 and entitled METHOD OF FORMULATING A FUEL COMPOSITION FOR USE IN INTERNAL-COMBUSTION ENGINES, which application is a continuation-in-part of U.S. patent application Ser. No. 13/217,171, filed Aug. 24, 2011 and entitled METHOD OF FORMULATING A FUEL COMPOSITION FOR USE IN INTERNAL-COMBUSTION ENGINES, which application is a continuation of U.S. patent application Ser. No. 12/105,164, filed Apr. 17, 2008 and entitled METHOD OF FORMULATING A FUEL COMPOSITION FOR USE IN INTERNAL-COMBUSTION ENGINES, which application claims priority to U.S. Provisional Patent Application Ser. No. 60/974,779, filed Sep. 24, 2007 and entitled MICROEMULSION FUEL COMPOSITIONS AND METHODS FOR PRODUCING THE SAME and also claims priority to U.S. Provisional Patent Application Ser. No. 61/036,007, filed Mar. 12, 2008 and entitled FUEL COMPOSITIONS FOR USE IN INTERNAL-COMBUSTION ENGINES AND METHODS OF FORMING USING SUCH COMPOSITIONS, each of which is incorporated herein by reference in its entirety for all purposes.

TECHNICAL FIELD

The disclosure relates to the field of fuel compositions. More particularly, the disclosure relates to fuel compositions and fuel additives for internal combustion engines.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram showing a new method for synthesizing and formulating a fuel composition for use in internal-combustion engines in accordance with the present invention.

FIG. 2 is a schematic diagram that shows a method for formulating a fuel composition on large scale in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides fuel compositions for use in internal-combustion engines, and methods of forming and using such compositions.

The fuel compositions generally comprise (1) a hydrocarbon fuel, such as diesel, (2) a polar fluid, such as alcohol, water, and/or other oxygen rich fluids, (3) an emulsifier present in an amount effective for the hydrocarbon fuel, polar fluid, and emulsifier to form an emulsion; and (4) a cetane enhancer, such as 2-ethylhexyl nitrate. The emulsifier may be selected from a group consisting of noncyclic polyol fatty acid esters and noncyclic polyol fatty alcohol ethers. In some embodiments, at least about half of the emulsifier is selected from this group. In other embodiments, at least about half of this group is mono-substituted. The emulsifier also may consist essentially of a single molecular species having both polar and nonpolar portions.

The methods generally include methods of forming and using the fuel compositions, including components thereof. For example, the invention provides methods of forming the emulsifier, by synthesizing and/or purifying components of the emulsifier. These components may include noncyclic polyol fatty acid esters and noncyclic polyol fatty alcohol ethers.

These and other aspects of the invention are described in the following four sections: (1) synthesis of noncyclic polyol fatty acid esters and noncyclic polyol fatty alcohol ethers, (2) purification of noncyclic polyol fatty acid esters and noncyclic polyol fatty alcohol ethers, (3) fuel compositions, and (4) examples.

Monoglycerides of fatty acids have been used for years as surfactants in a variety of food, cosmetic, and other formulated products. In most applications, industrial-grade monoglyceride compositions having 40-55% monoglyceride content have proven suitable. However, the present application in fuel formulations requires high-purity monoglycerides to yield optimal performance, and inexpensive monoglycerides to be economically practical.

Monoglycerides have been synthesized by a variety of methods. Unfortunately, these methods generally yield products that must be further distilled or extracted to obtain high-purity monoglycerides. Moreover, these methods generally are unsuitable for forming monoglycerides of unsaturated fatty acids, such as oleic acid, because of oxidative decomposition at the point of unsaturation. U.S. Pat. No. 2,022,493 to Christensen et al. discloses the conventional method for synthesizing monoglycerides, which involves the transesterification of triglycerides with glycerol and sodium hydroxide to form the monoglycerides. However, the product of this method is a mixture of 40-55% monoglyceride, 20-30% diglyceride, and a remainder of unreacted triglyceride. U.S. Pat. No. 2,132,437 to Richardson et al. and U.S. Pat. No. 2,073,797 to Hilditch et al. disclose two methods of increasing monoglyceride selectivity by converting the triglyceride to free fatty acid before esterification. However, the products of these methods are still contaminated with at least 20% di- and triglyceride, and the methods are considerably more complex than the conventional method. U.S. Pat. No. 5,153,126 to Schroder et al. discloses a method for making additional gains in selectivity by using a lipase enzyme as the transesterification catalyst. However, this method is very costly and difficult to scale up.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion, and a cetane-enhancer component. The microemulsion includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

FIG. 1 shows a new method 100 for synthesizing and formulating a fuel composition for use in internal-combustion engines. At step 102 a lower grade fuel is provided, the fuel is non-renewable content in the fuel composition. The fuel can be diesel. A non-renewable content including lower grade fatty acid derivatives (or surfactant) and/or other surfactants may be selected. At step 104, an alcohol component such as, but not limited to, lower grade ethanol (i.e. hydrous ethanol, and so forth) may be selected or provided. Then at step 106, a microemulsion having at least one of lower grade fatty acid derivatives is provided. The steps 102 to steps 106 can be performed in any order. The microemulsion is considered to be extremely fine colloidal dispersions consisting of micelles, or “bubbles,” of water and alcohol coated with a layer of surfactant.

Thereafter, at step 108, the fuel composition is formed or formulated by adding to the fuel, a microemulsion having at least one of hydrous component, renewable component, and polar component being present in an amount effective for forming the fuel composition. The microemulsion may include a mixture of oleic acid, ethanol, ammonia, water, and a cetane enhancer, such as 2-ethylhexyl nitrate.

These steps may be performed under conditions that would tend not to substantially reduce an unsaturated fatty acid or fatty chloride. Such conditions may include performing one or more of the steps in an inert atmosphere, such as a nitrogen atmosphere, or performing one or more of the steps in the absence of light.

FIG. 2 shows a method 200 for formulating a fuel composition on large scale. The method 200 may include refining crude oil 202 and through one or more refining process fuel is derived. The fuel can be straight run diesel 204. Similarly, lower grade fatty acid derivatives, such as, oleic acid, ethanol, and bi products of crude oil such as ammonia, water, along with cetane enhancer are blended to form microemulsion 206. The microemulsion 206 may include at least one of lower grade fatty acid derivatives that may be present in an amount effective for the fuel 204, alcohol, and water components to form a microemulsion 206. The fatty acid can be oleic acid. Then, at least 57 to 99% of fuel 204 i.e. diesel can be blended with 43-1% of microemulsion 206 to formulate a fuel composition 208. The method 200 may also include assessing the quality of the microemulsion 206 that can be done by analyzing at least one of an oxidative stability and contaminates in the microemulsion 206. And the diesel 204 can be a straight run diesel or an unadditized diesel. In one or more blending containers, the microemulsion 206 may be blended with fuel, water, ammonia, cetane enhancer, and alcohol to form the fuel composition 208 (final product). The microemulsion 206 may be blended in different volumes with the fuel 204 (or diesel) which can be 5%, 6%, 12%, and so forth. Further, the microemulsion 206 for formulating fuel composition may include a mixture of oleic acid, ethanol, ammonia, water, and a cetane enhancer.

The microemulsion 206 can be blended with lower grade diesel or fuel 204 by using inline blending process at a petroleum terminal. The inline blending process includes blending of the microemulsion 206 at the petroleum terminal(s) within one or more pipelines. Alternatively, the microemulsion 206 can be blended with lower grade diesel/fuel 204 by performing splash blending at the petroleum terminal. The splash blending may include blending the microemulsion 206 in a storage container (not shown) and then blending with the diesel 204 in distribution vehicle to splash blend in a transportation tank (not shown). The microemulsion 206 may also be blended with the fuel 204 by performing splash blending at a distributor i.e. by blending microemulsion 206 when blending the diesel (or fuel) 204 to have the fuel composition 208 for distribution.

The present disclosure provides a fuel composition for use in internal-combustion engines; the fuel composition may include a lower grade fuel component 204, and a microemulsion having at least one of hydrous component, a renewable component, and a polar component, which are present in an amount effective for forming the fuel composition. The fuel composition may enhance lubricity, corrosion, and water stability without the use of other additives and inhibitors. The microemulsion 206 is blended with lower grade diesel/fuel 204, water component, a cetane enhancer, an alcohol component to form the fuel composition. The disclosed method forms a new improved fuel composition that includes increased concentration of renewable contents. Further, the new improved fuel composition is formed such that it may reduce carbon intensity in the internal combustion engines. The new improved fuel composition can also dilute contents of aromatics, sulfur, phosphorus, and other contaminants. The new improved fuel composition may also reduce emissions of NOx, particulate matter, and other criteria pollutants. The improved fuel composition allows a flashpoint to stay below 38C for microemulsion concentrations greater than 1% but the flashpoint increases for microemulsion concentrations that are below 1%. The improved fuel composition forms spontaneously upon blending, and maintains clarity at low temperatures, upon freeze-thawing, and for prolonged periods. Further, the improved fuel composition can be biodiesel.

The disclosed method for formulating the fuel composition further includes optimizing the microemulsion volumes to be blended with a different quality of diesel or fuel. The method also includes optimizing the microemulsion 206 to blend with different quality of diesel/fuel. The disclosed method also includes optimizing the algorithms for microemulsion optimization based off crude oil contents and diesel refining optimization. The present disclosure also provides a method for allowing for the blending of renewable components upstream of distributer blenders. The formulated fuel composition results in increased renewable contents in fuel or diesel, and reduced carbon intensity. The formulated fuel composition also includes diluted contents of sulfur, phosphorus, and ash. The formulated fuel composition when used in internal combustion engines may result in reduced emissions.

In the preceding description, various aspects of claimed subject matter have been described. For purposes of explanation, specific numbers, systems and/or configurations were set forth to provide a thorough understanding of the claimed subject matter. However, it should be apparent to one skilled in the art having the benefit of this disclosure that claimed subject matter may be practiced without the specific details. In other instances, features that would be understood by one of ordinary skill were omitted and/or simplified so as not to obscure claimed subject matter. While certain features have been illustrated and/or described herein, many modifications, substitutions, changes and/or equivalents will now occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and/or changes as fall within the true spirit of claimed subject matter. 

We claim:
 1. A fuel composition for use in internal-combustion engines, the fuel composition comprising: a lower grade fuel component; a microemulsion comprising at least one of a hydrous component, a renewable component, and a polar component being present in an amount effective for forming the fuel composition; and wherein the fuel composition enhances lubricity, corrosion, and water stability without the use of other additives and inhibitors.
 2. The fuel composition of claim 1, wherein the microemulsion is blended with lower grade diesel, water component, a cetane enhancer, an alcohol component to form the fuel composition.
 3. The fuel composition of claim 2, wherein the lower grade fuel is diesel which is at least one of a straight run diesel or an unadditized diesel.
 4. The fuel composition of claim 3, wherein the microemulsion volumes which are blended with the lower grade diesel component is at least one of 5%, 6%, and 12%.
 5. The fuel composition of claim 4, wherein the fuel composition comprises increased concentration of renewable contents.
 6. The fuel composition of claim 5, wherein the fuel composition is formed such that it reduces carbon intensity in the internal combustion engines.
 7. The fuel composition of claim 6, wherein the fuel composition dilutes contents of aromatics, sulfur, phosphorus, and other contaminants.
 8. The fuel composition of claim 7, wherein the fuel composition reduces emissions of NOx, particulate matter, and other criteria pollutants.
 9. The fuel composition of claim 8, wherein the fuel composition allows a flashpoint to stay below 38C for microemulsion concentrations greater than 1% but the flashpoint increases for microemulsion concentrations that are below 1%.
 10. The fuel composition of claim 9, wherein the fuel composition forms spontaneously upon blending, and maintains clarity at low temperatures, upon freeze-thawing, and for prolonged periods.
 11. The fuel composition of claim 10, wherein the fuel composition is biodiesel.
 12. A method of formulating a fuel composition for use in internal-combustion engines, the method comprising: providing a fuel; and forming the fuel composition by adding to the fuel, a microemulsion comprising at least one of hydrous component, renewable component, and polar component being present in an amount effective for forming the fuel composition; and wherein the fuel composition enhances lubricity, corrosion, and water stability without the use of other additives and inhibitors.
 13. The method of claim 12 further comprising assessing the quality of the microemulsion.
 14. The method of claim 13, wherein the quality is assessed by analyzing at least one of an oxidative stability and contaminants in the microemulsion.
 15. The method of claim 14 further comprising optimizing the microemulsion volumes to be blended with different quality of the diesel.
 16. The method of claim 15, wherein the diesel is at least one of a straight run diesel or an unadditized diesel.
 17. The method of claim 16, wherein the microemulsion volumes which are blended with the lower grade diesel component is at least one of 5%, 6%, and 12%.
 18. The method of claim 17, wherein the microemulsion is blended with lower grade diesel, a water component, a cetane enhancer, an alcohol component to form the fuel composition.
 19. The method of claim 18, wherein the fuel composition is formed such that it reduces carbon intensity in the internal combustion engines.
 20. The method of claim 19, wherein the fuel composition dilutes contents of aromatics, sulfur, phosphorus, and other contaminants.
 21. The method of claim 20, wherein the fuel composition reduces emissions of NOx, particulate matter, and other criteria pollutants.
 22. The method of claim 21, wherein the fuel composition allows a flashpoint to stay below 38C for microemulsion concentrations greater than 1% but flashpoint increases for microemulsion concentrations that are below 1%.
 23. The method of claim 22, wherein the fuel composition forms spontaneously upon blending, and maintains clarity at low temperatures, upon freeze-thawing, and for prolonged periods. 